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Testing departure from Hardy-Weinberg proportions
1Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
Methods in Molecular Biology (Clifton, N.J.)
|February 7, 2012
Summary
The Hardy-Weinberg principle is crucial for population genetics and disease studies. Deviations from these proportions can indicate genetic associations with diseases.
Area of Science:
- Population Genetics
- Human Disease Studies
Background:
- The Hardy-Weinberg principle historically studied allele frequency changes.
- It is now vital for detecting inbreeding, population stratification, and genotyping errors in human disease research.
Purpose of the Study:
- To describe the Hardy-Weinberg principle and its common tests.
- To demonstrate step-by-step application of chi-square and exact tests using SAS, R, and PLINK.
- To discuss recent advancements in testing Hardy-Weinberg proportions for case-control studies.
Main Methods:
- Comparison of Pearson's chi-square goodness-of-fit test and the exact test for Hardy-Weinberg proportions.
- Detailed procedural demonstrations using SAS, R, and PLINK software.
- Exploration of novel approaches for case-control study designs.
Main Results:
- Pearson's chi-square test is sensitive to small sample sizes and rare alleles.
- The exact test is preferable for small sample sizes or rare allele frequencies.
- Deviation from Hardy-Weinberg proportions in affected individuals suggests disease associations.
Conclusions:
- The Hardy-Weinberg principle and its tests are fundamental in genetic association studies.
- Software-based implementation (SAS, R, PLINK) facilitates practical application.
- Testing Hardy-Weinberg proportions offers insights into disease etiology and genetic variant associations.
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This test is...
This test is...